The present invention relates to a stop-check valve for regulating the passage and the amount of flow of a fluid in the piping systems or machinery.
Swing check valves and gate valves are known to be the valves of frequent use in pipes, tubes and other forms of passageway, in which the check valves open and close the seats by their swingeable discs to prevent the return flow of fluids. These valves not only are simple in construction and can effectively check, but because there is least change in the direction of the passageway of the flow in and outside of their valve body and also there is possibility for the flow in whole amount during full opening, the check valves can minimize resistance to the fluid and thus possess the efficiency in facilitating particularly the passage of fluid as is in the gate valves. Such a check valve, however, does not have the construction and function capable of opening and closing for controlling the fluid and regulating the flow of the gate valves and the usual stop valves. The check valves are thus restricted in uses and for this reason, it is frequently required that a stop valve be fitted during the design of passageways in order to open and close and regulate the fluids, and hence an increase in expenses for equipment and fitting. Such a drawback requires thus the attention for an improvement and solution.